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      <td class="subheader-left"><a href="matlab:open idisp">View code for idisp</a></td>
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<h1>idisp</h1><p><span class="helptopic">image display tool</span></p><span style="color:red>idisp</span>(<strong>im</strong>, <strong>options</strong>) displays an image and allows interactive investigation
of pixel value, linear profile, histogram and zooming.  The image is
displayed in a figure with a toolbar across the top.  If <strong>im</strong> is a cell
array of images, they are first concatenated (horizontally).

User interface:

<ul>
  <li>Left clicking on a pixel will display its value in a box at the top.</li>
  <li>The "line" button allows two points to be specified and a new figure
displays intensity along a line between those points.</li>
  <li>The "histo" button displays a histogram of the pixel values in a new figure.
If the image is zoomed, the histogram is computed over only those pixels in
view.</li>
<ul>
  <li>The "zoom" button requires a left-click and drag to specify a box which
defines the zoomed view.</li>
</ul>
</ul>
<h2>Options</h2>
<table class="list">
  <tr><td style="white-space: nowrap;" class="col1">'ncolors', N</td> <td>number of colors in the color map (default 256)</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'nogui'</td> <td>display the image without the GUI</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'noaxes'</td> <td>no axes on the image</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'noframe'</td> <td>no axes or frame on the image</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'plain'</td> <td>no axes, frame or GUI</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'bar'</td> <td>add a color bar to the image</td></tr>
  <tr><td style="white-space: nowrap;" class="col1">'print', F</td> <td>write the image to file F in EPS format</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'square'</td> <td>display aspect ratio so that pixels are squate</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'wide'</td> <td>make figure very wide, useful for displaying stereo pair</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'flatten'</td> <td>display image planes (colors or sequence) as horizontally
adjacent images</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'ynormal'</td> <td>y-axis increases upward, image is inverted</td></tr>
  <tr><td style="white-space: nowrap;" class="col1">'cscale', C</td> <td>C is a 2-vector that specifies the grey value range that spans
the colormap.</td></tr>
  <tr><td style="white-space: nowrap;" class="col1">'xydata', XY</td> <td>XY is a cell array whose elements are vectors that span the
x- and y-axes respectively.</td></tr>
  <tr><td style="white-space: nowrap;" class="col1">'colormap', C</td> <td>Set colormap C (Nx3)</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'grey'</td> <td>color map: greyscale unsigned, zero is black, maximum value
is white</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'invert'</td> <td>color map: greyscale unsigned, zero is white, maximum value
is black</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'signed'</td> <td>color map: greyscale signed, positive is blue, negative is red,
zero is black</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'invsigned'</td> <td>color map: greyscale signed, positive is blue, negative is red,
zero is white</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'random'</td> <td>color map: random values, highlights fine structure</td></tr>
  <tr><td style="white-space: nowrap;" class="col1"> 'dark'</td> <td>color map: greyscale unsigned, darker than 'grey', good for
superimposed graphics</td></tr>
</table>
<h2>Notes</h2>
<ul>
  <li>Color images are displayed in true color mode: pixel triples map to display
pixels</li>
  <li>Grey scale images are displayed in indexed mode: the image pixel value is
mapped through the color map to determine the display pixel value.</li>
  <li>The minimum and maximum image values are mapped to the first and last
element of the color map, which by default ('greyscale') is the range black
to white.</li>
</ul>
<h2>See also</h2>
<p>
<a href="matlab:doc image">image</a>, <a href="matlab:doc caxis">caxis</a>, <a href="matlab:doc colormap">colormap</a>, <a href="matlab:doc iconcat">iconcat</a></p>
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<p class="copy">&copy; 1990-2011 Peter Corke.</p>
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